Cambridge International A Level Biology Revision Guide

Chapter 11: Immunity
10 a Rearrange the following statements to produce a flow diagram to show how monoclonal antibodies
are produced.
1 hybridoma cells cultured
2 mouse injected with antigen
3 mouse plasma cells fused with cancer cells
4 hybridoma cells making appropriate antibody cloned
5 mouse B-lymphocytes that recognise the antigen become plasma cells [5]
b
A monoclonal antibody has been produced that binds to a glycoprotein called tumour-associated
antigen (TAG). TAG is found in ovarian cancer and colon cancer cells.
The antibody is labelled with the radioactive isotope indium-111, ( 111 In). This isotope emits low-energy
gamma rays that can pass through soft tissues of the body. The half-life of indium-111 is 2.8 days.
i Explain how this monoclonal antibody can be used in the diagnosis of cancer. [3]
ii Suggest why indium-111 is a suitable radioactive label for this diagnostic antibody. [3]
iii Suggest how the antibody could be modified in order to treat a cancer. [2]
[Total: 13]
11 The table below shows the blood cell counts for four young female patients at a hospital. Each patient
has a different medical condition.
Patient
A
Medical
condition
an unknown bacterial
infection
Red blood
cell count
/ millions
cells
mm −3
White blood cell counts / cells mm −3
All white
blood
cells
Neutrophils
Lymphocytes
All B cells T cells
5.7 11 000 7500 3500 2000 1500
B HIV/AIDS 3.6 3885 2085 1800 130
C
D
acute myeloid
leukaemia
acute lymphoblastic
leukaemia
1.1 47 850
4800
(mature)
40 800
(immature)
3.2 156 700 450
1670 (of which 150
are helper T cells)
2250 350 1900
1250
(mature)
155 000
(immature)
400 850
245
Use the data in the table above and Table 11.1 on page 231 to answer the following questions.
a Make a table to show how the blood cell counts of each of the four female patients differ from the
typical values and the ranges given in Table 11.1. [3]
b Explain the differences that you have described in a. [8]
c Patient A had a blood test before she fell ill. The red blood cell count was 4.6 × 10 6 mm −3 and the white
blood cell count was 7000 cells mm −3 .
i Calculate the changes in cell counts between this test result and the result shown in the table above. [2]
ii Use your results for i to calculate the percentage change in the numbers of red and white blood cells
in 1 mm 3 of blood. [2]
d Blood cell counting is an automated process and results can be available very quickly. Suggest why the results
for a single sample of blood taken from a patient on admission to hospital should be interpreted with care. [3]
[Total: 18]